Sorry about the lack of updates people - a combination of lack of internet, switching countries (back in France again), and heart surgery has all contributed.
Anyway, as its my first day back from hospital, and i'm supposed to be resting (pfft!), so i thought i'd post up the 'what went on' and pictures etc.
So, the welding got sorted in the end, the passenger side took about an hour or so - tack welded a mild steel strip into place at the, beat it with a ball pein hammer until it took the shape of the inner arch, and filled around it. It's definitely a nice, strong weld, although it's not exactly pretty - thanks mainly to the fact that the MIG welder we were using couldn't supply the wire feed at a slow enough rate, and was having thermal overload issues (ie, it was crap).
The drivers side only needed two patch sections welding in as the grotty looking metal on the inside was...well, redundant, as the outer arch job had filled almost all the gash, and was strong enough. MIG actually looks pretty simple to do, as long as you prep correctly. I may have to buy a MIG welder myself.
At the same time though, the curious (yet sizeable) oil leak, was found, and fixed. Turns out that the guy that did the work on the car, fitted the cam cover gaskets (rubber, re-usable), fitted them SO badly, that it was p*ssing out oil from both sides, at both ends - soaking the belt tensioner and crank pulley & gear at the front, and down the bellhousing at the back. The central gallery plugs were also loose, so new washers, and some loctite sealant sorted that out. The only casualty in that regard, is the gallery cover - it's crunchy like a rich tea biscuit, so it's hit the bin. If i'm doing the IS300 Coil-on-Plug mod, then it will be redundant anyway. The other casualty, is the Cam Position Sensor Cover. It disintegrated in my hands, literally. Nothing left of it.
At the same time, i took the opportunity to drain the coolant, and fit 90% of the Samco Hoses. I'll take pictures of the engine bay as it now stands tomorrow.
For now though, welding pictures, and one of how it looks in my courtyard...and alongside Shaz's (currently my D/D)