Gravelface, I appreciate your input and if my circumstances were different I would probably just have done it and not looked back.

As it happens my livelihood will be compromised by a brush with the law and as such I really cannot afford to do anything dicey.

The comments and opinions in this thread has turned me somewhat off this option, but if I do follow up on it I will either purchase the whole thing assembled from a licensed FFL or get a letter from the ATF saying the parts I plan on putting in the gun puts it comfortably inside the compliance area.

What I really just want is a bullpup shotgun because it pushes my gadget button to the max. The KelTec KSG looks fantastic, but it is getting mixed reviews, is almost impossible to get a hold of and an acquaintance's experience really put me off KelTec products.

As a side note, I really trust you guys on this forum which is why I ask these questions here, thanks for your frank opinions.