no it will not work, the cylinders on the GTs block and the GT block are different, and the bolt holes will not match up for the mounting of the head on the block...plus the valves are too big for the GT block...nice idea...you aren't the first one...but sorry, it doesn't work. Now, if you had say a 3rd generation supra with a 1jz-gte, a popular and perfectly matching and functional head swap would be to put the head off of a 2jz-gte on the 1jz-gte block...it is said to give 30 - 40 hp on the supra 1jz-gte...but again sorry, it doesn't work on the zz series of toyota engines