I ran kine in the tub for awhile last year.
I drilled a 5/8” hole in the tub forward if the centre seatbelt mount. Used a piece of 1/4” x 1-/2” flat stock about 2” long, drilled a 5/8” hole through the centre and welded a jut to the underside. Drilled 2 more holes at the end of the piece and bolted it to the underside of the tub. Laid the tire in position and used a piece of 1/2” ready-rod with a “tee” welded to the top. Took about 15 seconds tops to get the tire out without tools.
It sounds like you aren't doing this anymore. If so, why not?
