Thats really nice! I've half pie been thinking of doing one of these in a 'what if' New Zealand scheme. Apparently we cam pretty close to getting Leopard 1s but the government decided to purchase the Scorpion instead.
I started it around the same time as the M113. Was a great kit and nice easy build. It probably took the equivalent of 5-6 days in total. I kept the weathering to bare minimum...just used some turps mixed with ground up pastel chalk and gave it a few flicks with an old paint brush