You could also use a grant to collect wort from the mash via gravity then just suck the grant out into the kettle whenever it fills up.
grant=little bucket.
Don't know that i've ever seen anyone "sparge" like the fella in the link above.
I usually let the wort run out the bottom of the mash/lauter tun slowly while I pour the sparge water over the grain bed [using a sloted spoon to prevent digging channels].
Its still hot right? just dump it into a bucket, put the screen in, then boil for another 15 minutes and collect your wort as normal. I left the screen out once but I caught it before the start of the boil.
I'd like to swap spreadsheets with ya. my email is babinson @ yahoo dot com
mine is not fantastic but the only thing I really wanted to do was to be able enter my grain bill in percentage and have it give me the mass [which was accomplished]
there are some other things like bucket...
I've got one of those without the sight gauge. I just cut an inch off of the down tube and I get clear beer (after an intial purge, which I use for my TG)
I ferment in a chest freezer so its nice to be able to just push into the corny's with CO2 (no lifting)
I found that a lot of wort/beer is lost when you use a keg for kettle because of the dish.
In my opinion, a flat bottom purpose built kettle is worth the extra money. there are some cheap italian jobs on the market but they have a funky thread pitch on the fittings so you'll most likely want...