The 'instructions' included with the kit are little more than a one-page parts list and four poorly reproduced blueprints - two for the heater install and two for the front canvas cover install. There is no 'step by step' instruction, the closest you will get to that is the link Opie posted above.
If you're missing the blueprints, they are online - one of Bjorn's photo links here somewhere (maybe he'll post it). They are definitely useful, and if you study them carefully you will see that they show where each part goes and show which fasteners should be used to install them.
The TM exploded view drawing you mentioned shows component placement better than the blueprints, IMHO. For example - The blueprint shows the circuit breaker mounted under the dash near the passenger's side. The TM shows it on the driver's side firewall, and the wire lengths included in the kit fit best with it there. The power switch and control cables, too, are best under the dash to the left of the steering wheel as the TM shows, not as the kit blueprints show... Also, as OPCOM pointed out, the duct routing should be crossed per the TM. Maybe the fact that these heater kits were designed for the old gasser deuces, not the newer multifuels, explains the discrepancy between the blueprints and the TMs? I don't know, but I used the TM for placement reference, the blueprints for proper wiring and fastener usage, and the tech article for pictures, tips, and guidance - and I'm very pleased with my installation.
On my deuce, I had very few holes to drill... There were pre-punched and/or drilled holes for the circuit breaker, resistor, wiring firewall grommet, and ducts. Holes were needed in the fender and frame for the JATonka heater mounting bracket, in the firewall to mount the curved duct damper and the deflector box, and under the edge of the dash for the switch and cables. ...And of course the side panel for the air scoop and screen.
Between the blueprints, the drawings in the TMs, and the photos and instructions provided in the tech article here on SS, I think there's enough to figure it out and get it installed to your liking.
Regards,
Jon