Interchangeability - expert help required.

[KUYTD 10]

Afternoon all.

I'm still after a year or two thinking about it, looking to sort my GS300 box, it's the weak point and really just a matter of time till it takes the car off the road.

Refurbishing isn't an option, just too expensive considering the value of the car, so I'm looking at getting a low mileage salvage box to pop in and have found several of the 6 speeds around. It's an A960e, and this was also in a few other models, one of those being the IS250. But I'm really confused over part numbers, good old Wikipedia only shows one entry for the A960e, but each seems to have a different part number. I believe the one in mine will be a 35010-30b20, but the sticker on the IS box says 35010-53100, what if any difference is there?

Also, in terms of bolt patterns and overall fitting with the ECU, is there any chance an AA80e 8 speed from the LS would fit and work?

Would really appreciate any feedback.

Thanks

[KUYTD 10]

I suppose I should add...

If I get an actual GS300 replacement I'm looking at 1k plus for low mileage, but I can find low mileage IS250 ones for half that.