hi guys,just a little something to rattle your brains

i'll start from the beginning, last year i fitted heated grips to my AT and just after fitting them i blew a rectifier whilst they were in use. then during february of this year i blew another rectifier whilst the grips were in use. i decided to disconnect the grips thinking this caused the problem but obviously not as i just went through another rectifier without the grips connected! i decided to check the bike out once and for all!!
stripped it down checking all wiring connections etc and all was in order. i took off the generator casing to find the generator to be discoloured on half of it, so i ordered an aftermarket one locally. it is an electrex generator and when i went to fit it i noticed it's slightly narrower than the original making the bolts too long by about 3mm. i checked the website of electrex and apparently i have the right one for my bike part number g07. so being a bit pi**ed i thought i'd look up price of original. when i went to take the engine/frame numbers i noticed that the engine number starts with rd04 and the frame starting with rd07, is this normal? it's a 2002 model rd07 but is the engine number correct for this bike? it was one owner from new when i bought it with only 4k on the clock. just wondering if this is maybe why the generator is slightly different? any help greatly appreciated as i'm supposed to catch the ferry to spain on the 8th nov so i aint got loads of time!
thanks for any help in advance. kevin