Some sharpies react with the thinners in paint and may run, but do try a test piece and just do very light coats with a good wait in between, even standing by with a heat gun or hair dryer may be helpful
The screen shown position of the strap on the chest plate is one large ridge and 4 and 1/2 small ridges, as the ATA chest plate is different to most you can only fit one large ridge and 2 and 1/2 ridges on the chest plate.
Depending on height and fitting some cut out a section on the rear of the thigh and calve, this is screen accurate so it is approvable. AS I have long legs I didn't have an issue and to this date not suffered an armor bite, but I am one of the lucky ones
You can see the sections removed in the photo below
There had been a lot of parcels lost or missing pieces sent to the US, hence why doopy's will no longer post to the US, we have no problems with parcels getting here in Aus
There was no template, I found some rough measurements over at the French 501st forum here, I then used the SE-14R as a guide for sizing and took it from there, below is the photo posted by RS propmaster of what it looks like
With my ATA and my skinny arms I just added a couple of pieces of foam inside to keep the forearms from sliding around. If you glue Velcro to the pieces of foam you can remove them for washing
The pieces of abs are glued to the back section, they fit snug behind the front section when closed, the elastic keeps it all tight together and the abs strips behind the armor stops the sides being forced out.