Hi Norman, As I posted recently, I happened across an early Trillium 1300 at an auction sale in October this year. As I own a"June 73" model I was curious about this one. Unlike mine it did not have a date of manufacture, but it did have a sticker with the serial number...I think it was about 430. The tail-lights were not the horizontal Bargman of the 73's thru 80's...they were trapezoidal and shorter in width. There was no frame extension to a rear bumper, but other than that, it was identical to mine. Since the front jalousie and gravel guard were gone and replaced by a piece of plexiglass, I didn't see it as a restoration project...despite its history as one of the first. Judging from my serial # and the one at the auction, I'd guess that this early model was a '72....maybe a '71. (My bill of sale is for Oct. 72- so I guess folks were ordering them a bit in advance even then).
I hope this sheds a bit of light
on the time frame of these great rigs.
I recall last year we had one of the original principals of the Markham ON operation postin on this site,looking for Trills to measure the interior dimensions prior to setting up manufacturing ops in the US. He might be a source of information too.
Good luck with your quest...Alistair