Has anyone just made their own? I need one and bought Summit's: http://www.summitracing.com/parts/SUM-G1369/ However, at the risk of sounding like a complete idiot... I can't figure out how to mount it , unless the 2 predrilled holes are not actually used for mounting it? If that is the case, I will drill my own I suppose. But back to topic, has anyone made their own? I have the materials and tools, just not sure exactly what it should look like.

Get some heat reflective tape and put it on the solenoid closest to the header

Most mount to the two mounting bolts that attach the starter to the block
Some use a 3rd point at the front stud that anchors the brace to the block

Fix the problem and forget the heat shield.
When the motor is tuned properly the exhaust should never get hot enough to bother the starter.

Even with headers? Not questioning you Don, you ARE the exhaust guy after all . But this isn't stock exhaust we're talking about

get the one from GM it's the one for Big Block and small blocks.
$150 bucks it's about 5lbsTOTAL and is so small it's not close to the headers any more.. turns a 11.1 383 sbc over at about 1000rpm.. perm Magnet..

you will never look back..

untill then i made my heat shield. out of sheet alum.
worked for a long time.. till i just wanted to remove even more steel from the front end..doing this shaved another 12lbs off..
going over my old notes i took over 230 lbs off the front end...

What I did was wrap the starter up with fiberglass header wrap, then wrap that with some aluminum heat shielding I got from the junkyard. The stuff I'm talking about is like really heavy, dimpled aluminum foil. The kind I like is often found on the A/C boxes and firewalls of '99 and newer Ford diesel pickups. I also use that stuff to wrap my headers with.
To hold it all on the starter, I used a couple of big hose clamps.