ok, i figured out how to do it, if anyone is interested:
download CWCHEAT from here
1.obviously put the MS_Root folder on your memory stick root.
2.reboot your psp and hold R and enter recovery mode, go to plugins and enable cwcheat.prx [pops]
3.crank up your popstation eboot.
4.hold the select button for a few secconds.
5.select manage memory cards from the cwcheat menu that comes up.
6.then choose either "save memory card 1" or "save memory card 2" to memory stick depending on which save you wish to use.
7.exit the game and go to usb connect in the xmb.
8.navigate on your pc to ms0:/seplugins/cwcheat/mc/ and your exported save will be here, in my case iit was called "slus_00776-0.mcr".
9. now just rename this save to match whatever pcsxbox is using i renamed it to "Metal Gear Solid - Disc 2 [SLUS-007760.mcd" and slapped it in E:/SAVES/PCSXBOX/Metal Gear Solid - Disc 2 [SLUS-007760/.
this may well be common knowledge but seing as no one replied i guess not.