SI? = unsure but may just be TSI
M6F = Manual 6 speed front wheel drive (the R models are M6A = manual 6 speed all wheel drive). The DSG's are D6F, D7F (for GTI) and D7A (R model)
GTIBM is just a code they seem to refer to in some VW brochures. Some say GTI BMT and others say GTI BM. Same code regardless of whether its a GTI or R so seems worthless.
I just purchased a late 2015 GTI PP a few weeks ago, so will check my build sticker and compare to yours. Mine is a DSG (already regretting it....boring) so should be D6F for the transmission code. My engine code should be 169kw so will see if I have the SI bit.
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