Thanks for all the replies. I do have the belt in lock mode, but I still can't get as tight a fit as I can on my other vehicle. I put about 230lbs of weight on the Car seat and feed the belt in, but it's still not very tight. The locking mechanism doesn't have fine increments.
I surprised to hear you say that. I went out in the garage and pulled the seatbelt "all the way out" to "switch" mine over to locking mode and it ratchets in very "fine" increments, 5 to 7 clicks per inch. Sounds like I'm spinning my 3/8 drive ratchet by hand.
(someone else please check and verify this on another Vette)
If your sure your in locking mode and you still can't get it tight, there is one other method we use.
1. Put the belt in "locking mode" and push it through the pathway.
2. Stop when the latchplate gets about 3 to 4 inches away from the latch.
3. Pull the seat back toward the open door slightly then lean on it hard with your chest or belly and "Rock" the seat toward the latch while guiding the latchplate into the latch..
4. With a little practice you can get it very tight this way.
Not getting it as tight as your other car may be because you have more "cushion" to depress in the other seat, but I have gotten CP seats very tight (hard to move side to side) in Corvettes
The new latch system (now on every seat manufactured) is great, but older seats don't have it, so you will still need to get it tight with the belts.
Hope this helps.