Sound decoder trouble...

[TenX]

I have two  Bachman DCC equipped diesel locos that I want to add sound to. My local shop sold me a kit that he was sure would work. Said it had the correct 8-pin connection- but when I opened them up there appears to be no 8-pin header anywhere to plug this board in. Both have the same decoder board in them, so I assume I'll have to replace them with sound-equipped decoders? I would appreciate any definitive answers anyone can give me? The first one is a FT A-unit model #60112 and the second is a GP30. Both have a board labeled H601X-PCB01 rev C dated 01/06/04 . I'm quite comfortable doing whatever work it takes to hardwire a new decoder and make mods to make it fit with the correct speaker. Just need to know what parts to get and what pitfalls I might encounter. I should also add that I don't need anything fancy because I'm running an EZ controller and only can use a few basic sounds. Thanks in advance! Oh and btw - is there a matching Bachman FT B-unit that is already DCC sound equipped? If so, would it make more sense just getting that?