Tom, if you are referring to the "doghouse" conversion for the M113, then I can say a little about it. The conversion kit was designed to fit the Academy kit, but it may fit the Tamiya offering with a little work. The top plate on the two kits vary slightly, so there may (and I stress may) be a fit problem with the how the resin parts mate up.
The majority of AEF conversions are designed particularly with a specific kit in mind, but that doesn't alway equate to an "only" fit. For example, my experiences with the M60-based conversions is that they can be "adjusted" to fit the Esci kits, although they were designed for Academy's offerings.
Just trying to help what little I can. If in doubt, you can contact Tony at AEF, and he will probably answer any questions you may have,
Dave