After various supportive replies from NSXers who "felt my pain" I was reassured that in fact there was NO unique tool designed to do this job and that YES it was time to actually use my brain. I ended up cutting a plastic cup into two spoon-sized pieces (one for each size piston) and was able to use these pieces to slip the boot over the piston. Felt great about myself for at least 24 hours. If anybody is interested I can take a digital photo of the plastic pieces. BTW the compressed air is for removing the pistons during disassembly.