i ran a post recently on this testastretta into a 748 frame type subject, apart from the already mentioned wiring loom etc, you will need to ensure that your using a frame that was orignially testastreta engined frame as the cross bracing is differant.
however i understand that this can be sorted out if you take your frame to a frame builder to alter, of course youl need a pattern from the right type of frame.
if you opt against this project id be interested in the engine you have ldentified?