The real impact of tg 20...

It would have been in the 70's when I used it Scaftek, remember when the ledger was done up it pressed into the standard, what impressed me about it was like T/F and Readylok you could set out the standards where you wanted but it was much quicker to erect than either. With a bit of modifcation on the transom plates I think you'd have a good inexpensive system.