When I bought my car I assumed it was just a standard 154 conversion but in talking with the original owner it appears to be from a Chaser. The shifter is a little "sloppy" but the car came with a shifter rebuild kit, but I'm used to toploaders and this one is some sort of short linkage setup. Any chance someone here is familiar with this version of the 154 or possibly has an exploded diagram of the setup before I pull the tranny and attempt to rebuild the shifter? Even some pictures would be a huge help.

 

RyanV here...ex-longtime Starquest a-holic

You have the 'tripod' style R154. You can use the 95+ W58 shortshifter. That's what I've been using.

Other than that...I'm not sure if there's an actual shortshifter for the late model R154..and if there is...it's probably gonna come from Japan.

Check out horsepowerfreaks

 

theres not much to "rebuild" on the tripod shifter I dont think.
make sure the big bushing on the bottom of the shifter is good and that the bolt holding it in is secure. then i would make sure the bolts supporting the tripod is secure.
mine just starting having some slop on my w58 and the bottom bushing and bolt are good.
it used to be 100% no play a month ago, so i suspect one of the tripod bolts is loose but I haven't crawled under there.
do let us know if you find the exact cause. good luck.