Engine tin hole plugs..., Where to find premade plugs that fit holes in engine tin?? Options

[second wind]

Hello all....so I went on the March 6 SoCal mini rally and it was a blast car ran great....on way up to 6.500 feet on Mt. Baldy I kept an eye on my cylinder head temperature gauge it was fine....even going down as the elevation went up....but glanced at oil temp gauge and temp was through the roof into the red!! Once we stopped and took a break one of the gurus looked at my engine to see where the problem was and he noticed that all of the holes in my engine tin were wide open....blower hose holes...rain gutter drain holes....fan belt adjustment hole....just a bunch of wide open holes. He said there you have it....your cooling fan efficiency is cut in half by all of those holes...plug 'em up and you will definitely see improvement in the oil temperature. So anyone know where to get ready made hole plugs for these holes? Would be nice to just plug 'em in and cure the issue.....thank you very much and would love to hear more comments about oil temp cooling tricks.
All the best,
gg