5.2bhp engine won't provide enough power/speed, unless you go for a two stage pump (high flow until pressure builds, at which point high flow pump dumps back to return, and low flow pump continues at higher pressure), but that kind of system isn't cheap/common.
You could run it of the fergie hydraulics, but you couldn't have it on the 3point linkage, as the only way you'll get hydraulic pressure out a TE20 is with the linkage at full height.
Be far better/cheaper to buy a PTO driven pump, which if buying new, I'd suggest White House Products in Port Glasgow, who can supply all the other bits you'd need aswell. But you'll need to know what displacement pump you'll need, which if you drop me an email (moray<dot>cuthill<at>googlemail<dot>com, I'll dig out the spreadsheet I've got for doing flow/rpm/hp requirements.
Last log splitter I built had 14t real splitting pressure (not the usual theoretical rubbish spouted by sellers, which is only possible if you have a stupidly high pressure pump, which nobody ever does!), with a 30sec cycle time for a 2ft ram.
Regarding the blade, it depends what you're splitting. A wedge is only good for relatively straight grained wood, which splits easy. If you're trying to split knotted/twisted grain, then a knife blade is far better, unless you have lots of pressure to force the log through.
And don't even attempt a multiway blade unless you're only ever planning on splitting softwood!