well, raincoat .5 will not flash the entire thing. you must make a 1mb bios. use x2bm (x2 bios manager) to make the bios 1mb (x2 5035 is a 512k bios). you MUST make it a 1mb image for it to flash the winbond with raincoat .5
now, if you want to retain the original bios, you just put the 5035 file in the raincoat dir. no editing needed. flip the switch to the side you want the bios on (preferably the a19 to gnd as it stresses the mcpx less), and flash. the bar will flash to 50 percent slowly, and then flash the last 50% very fast.