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3speedslow nope, different frame. The one you see here is one I bought off CL out of Birmingham.
Not sure on soaking frames in Evaporust. I use the crap out of that stuff, but it says pretty clearly on the instructions, you need to rinse (and if I recall, brush) off after soak. Can't do that inside frame tubes, so I've been skipping.
My method, which I've used with great success, is really close to what @
capnjonny describes above but maybe a bit less mechanically harsh. Get some ultrafine 0000 bronze wool from the hardware store and a few old toothbrushes, plus a slightly larger brush. Get a small bucket with a couple shotglasses full of your favorite car wash liquid and an inch or two of water. Also use a bottle of Simple Green HD, which is alloy-safe.
I prefer to do this with a headset and fork installed so I can toss on crap wheels and roll the frame outside to stand up. I'll usually stuff a red shop cloth into the seat tube and head tube to prevent water entry. I spray the tubing down with a solid coat of Simple Green HD. I scrub the crap out of everything with the larger brush, all tubes, all nooks and crannies. Then I spray all the lug joints and seams and use a smaller toothbrush to scrub those a bit better. Then use the car wash tube and alternate dipping and brushing. Rinse it all off.
One tube at a time, I'll re-spray with Simple Green HD, and use the ultra-fine 0000 bronze wool while the tube is nice and wet and slippery and with lightest pressure, run the bronze wool across the tubing. What this will do is similar to wetsanding, the rust particles are large and will rub out before the clearcoat (if any) is impacted. It's not dissimilar to using a blade to remove the rust, but safer ... what I've found is, using the bronze wool will leave any adhering paint intact, so this is great for removing surface rust without impacting any paint that's clinging on. This is especially good for top tube cable clamp rust.
THEN, at the worst spots where rust is clearly visible, Naval jelly or evaporust wraps (wet a paper towel with it, wrap the tube tightly, then saran wrap that to abstain evaporation) should be used to treat the rust.
Once complete, the bronze wool is so gentle on the existing paint, you can use a compound to rub out the paint, bringing any unrusted paint back to a nice luster again. Then follow-up with polish.
But in your case, you will probably want to take a little 000 fine bronze wool (not 0000 ultrafine) to target those lug joints. I would consider using a Dremel with a small wire wheel disc on the TT cable guides and at the head lug and seat lug joints. Then spot-treat until you can get the frame refinished.
I prefer real paint. That's just me. Powdercoat, while strong, can rust underneath. Once it's done, it's done. Trying to remove the powdercoat again is a bear.
This is just my 2¢ of course, YMMV