I purchased a seat foam kit for my 1972 240z awhile back and find it to be too stiff. Has anyone trimmed the foam to make it more comfortable and plush. I was thinking of taking about removing about 1 in from the seating area so that you will sit down in the seat more. What techniques have been used to trim this foam.

Seat cover fit might suffer. In essence, you'll be increasing the height of the side bolsters by 1 inch. The centre panel of the seat cover would end hanging in space above the carved-out foam. Occupant weight will force the cover down onto the foam, but the look (baggy) when the seat is unoccupied might make you wish you'd never tried it. I suggest that you run the idea by an experienced auto upholstery pro before you break out the carving knife

Dou you have any spacers in the mounting hardware that can be swapped to the bottom side of the seat mount?

Any supplier i should consider before reconstructing both of the seats on my 1972 240z?

https://www.thezstore.com/datsun-240z-1972/product/5900/seat-upholstery-kit-w-velour-insert-left-and-right-red-72-73-240z

Here's something to read through. This guy is something else, he don't know half arse hence the name Hardway.

The kit I purchased was from Motorsports Auto. I had to remove all of the spacers so my head did not hit the roof. As mentioned, I want to contour the seat foam so I sit down in the foam and not on top of it. The foam is very stiff and does not conform to your body. Looking for suggestions as best method to contour for foam.