You van's front is probably sagging and not at factory height.
You will want to re-index and adjust your torsion bars, then get an alignment. There are several guide that have been linked below on how to do this, but here are some notes on the USA spec van that do not seem to be mentioned in other guide for the JDM versions.
Jack up the van as high as you can get it. Use "V" headed jack stands on the front round tube cross-member under where they
bolt to the frame (as specified).
For the USA spec L300, you will need to at least loosen the back of the fuel tank, and then lower the front of it. Be sure to lower only as much as you need to gain some room. Do this when the tank is low if possible. A section of wood and a scissor jack are good to lower and support the front of the tank. The alternative, and in this situation, probably desirable is to drop the tank and restore it with new interior coating. POR 15, makes a tank sealant kit that I used. I will do a small write-up on how to do this later, or ask if you need help sooner.
After the tank is lower/dropped, you can then remove the front tank mount. You will notice that it has three bolts; one on the outer side and two on the inner side of the mount. They are 14mm short bolts with washers. If you do not drop the tank, you may need to use a swivel joint and some extensions to reach the outer bolt. Do this by going on the outer side of the tank. You will need a good spot light to be able to see up to the bolt. The other two inner bolts can be reached by a short socket and a standard ratchet. You will kind of reach over the inner side of the tank and be able to push up enough to get them loose.
When you have that removed follow the re-index procedure.
About the re-index procedure; do not make the "special tool" with the modified deep socket, it is not needed, but a deep socket is helpful to tighten up the adjustment nut when adjusting after re-index. You WILL need two 17mm closed end ratchet wrenches. They do not have to be the expensive ones.
1. To get the DRIVER'S SIDE torsion bar adjuster lock nut loose, you can use one of the wrenches, and a standard length breaker bar to use as a pry bar. Just position the wrench so that you can use the transmission end to seat the end of the bar against, and be able to move the wrench that is on the lock nut. BE SURE that you don't contact the electrical connectors that are mounted on the transmission side. Once you have it loose, you will not need the pry bar.
2. Passenger's side: Easier, but you do have to contend with the exhaust (catalytic converter). Just use the pry bar technique and find a spot on the frame where you can pry.
3. When you have re-indexed, reinstall the tank mount. Put some grease on the body contact area of the mount for anti-corrosion purposes. Then install mount and bolts. Be sure to tighten them to a firm level. Torquing them is not necessary, as long as they are firm.
4. After the tank mount it in, but before tank is put back in position/installed, re-index and then do initial measuring and setting. The re-index guide details this.
Other notes: You can pull back on the torsion bar rear mounts when they are loose, they will slide off with no effort. Be sure to pull back just enough to be able to more past on spline, and then do one more. The guide is correct, 2 is the limit. The passenger's side (USA spec) adjustment rod will have just enough thread to get the bolt back on. For the initial set, set both side the same, and be sure to reinstall the lock nuts too. Use the open end of one of the ratchets to hold the adjustment nut from moving while using the closed ratcheting end of the other one to tighten the lock nut. Be sure to make sure that all the rear and front tank bolts are tight.
Once the re-index is done, drive it for 20 miles, and then fill up the tank and follow the adjustment procedure (adjust bars when tank is full to account for load). Make sure that you have only the normal weight in the van (factory spec weight distribution).
RE-INDEX:
http://www.delica.ca/forum/re-indexing- ... -4051.html
(also here:
http://www.delica.ca/forum/l300-torsion ... -6206.html)
ADJUSTMENT (they spec 45mm, but follow your FSM):
http://www.mdocuk.co.uk/forums/viewtopic.php?t=19608