My present guide is like the one you describe from HD. If you attach it to a 1/4" X 8" wide, piece of birch ply (the good stuff), then rip it off you will have a good guide. The saw side will be cut so that you can align it directly on the marked line and the other side will give you plenty of clamp room. My saw is a Skil worm drive so, I cannot clamp on the guide its self. You may be able to, though.
To attach the ply to the guide, I counter sunk holes in the bottom side and drilled up through the metal guide and through a piece of 1/8" hardboard that just fits in the guides shallow trough. I used small bolts and nuts, about 30, to hold it all together. It's been straight for about 15 years.
The worm drive has two handles and I find it easy to keep the saw tight against the guide. You may want to check to see if your blade is square with the guide edge of the saw's shoe/plate. Another thing is that some blades tend to wander due to the set. I'm a big fan of Tenryu blades. They seem to have a good set. So good that I get minimal tear or or splintering on the off cut side.
Even as good as this guide is, I still feel the need to do a final cut at the TS. that's why I'm making the new guide....to save that TS step.
'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton
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