Compaq R3000 motherboards question

The R3000 laptops come in various motherboard references as 370494-01, 370495-01, etc... my question is can I replace my original motherboard (370494-01) by for example the 370495-01 one since the main differences between them are the firewire port , the nvidia chip and the memory size of the vga chipset. In another words does the 370495-01 (or another one) motherboard will fit the original cover and base enclosure (physically speaking) and is it compatible with the remaining parts (cpu, RAM, fan, pcmcia etc...)
Thanks.