Very glad to hear things are OK. Good luck with doing the hot work, soldering/brazing are not the same as welding. The first two involve the addition of a lower melting point metal to the original metal, this usually involves the use of a flux to prevent oxidization. Welding involves melting two similar metals so they fuse together as one.
Best of luck with moving your engine from it`s shed. Hoping your kart works well, please use ropes and pulleys and stay out of the way. 700 Kg of cast iron can make a mess of a man, even at very slow speed.
My build is slow but steady, I`ve finished the injector and pump and I will post some pics tomorrow.
Bob