Ah, finally someone else than me in the Quake community with some taste.</ass> You know, I kind of did this in a (afaik) lost testmod, which made the playermodel visible, with proper up/down looking and everything, you could even shoot yourself in the foot, literally (polygon collisions). The problem I had not predicted, which I'm sure you've forgotten about as well, is that all that needs to be clientside, or all aiming and movement will be lagged in multiplayer games, and you won't get even close to the awesome immersive experience you're after. When I made my testmod (called Supertorso, cause it was based on the idea of segmented models from Quake 3, but took it a step further, with making the arms separate segments as well), ClientSide QC wasn't implemented to DP yet, so I got sad and just threw it away. Nowadays, there's inofficial CSQC support in DP, which no one (thus far) has had the guts to try and figure out, the entity side of it that is. So, there's few people who can help you. The best you could probably do is ask a fellow called TimeServ, he made a few clientside mods for FTEQW, unsure if they had any entities (probably just HUD and effects mods), but you could always try. He works with FTE, rather than DP, so ideas and implementation will most likely differ a lot.
A good ol' word of warning: You *want* to be fairly experienced as a coder and/or QC junkie before you get too deep into this.
Good luck, and I hope to see all and any progress reported either here or a new thread!