One thing to think about. You mentioned the 4.3 engine to be cheaper. You also need to take into account all the other stuff you will need to get done with the 4.3 that isn't needed with the 1.6 swap.
The 4.3 will need a something like a th350 tranny, you need to rig up a new cooling sytem because there is no way the suzuki radiator is gonna work. New motor mounts, Also the 4.3 requires some kind of extra lift. I think with the 1.6 you can get away with a simple 2 inch body lift, maybe even a small shackle lift (not positive though) With th 4.3 I believe you will probably need at least a 3 inch spring lift, or possibly SPOA for oil pan clearnace. I'm really not sure about that though. I don't know if frame reinforcement is an issue or not. What kind of fuel delivery system would you use with the 4.3? Tuned port or carbed? Also you probably will want to end up beefing up your axles with a 200hp 4.3. Either keep the Suzuki axles and beef them up with the many options front and rear, or swap the axles for some beefier unit. Although this isn't absolutely necesary. www.ishopper.com/suzukiconver
That website is Lighting conversions, they started the 4.3 swap stuff, they sell a basic kit for 900 some bucks, I think everything that you will need will cost a good $2000 however.
If you can afford it I think it would be an aweome swap, otherwise if your 1.3 is on it's last legs I would suggest the more economical 1.6. 1.6 you are looking at maybe 500bucks max not including engine.
Hey, I'm doing a 4.3L conversion and if you have the motor all you need is a 3" lift (Recomend a SPOA),
Transfer case bracket $300.00
Cross members 100.00
Frame mounts 150.00
Motor mounts 150.00
Throttle cable 30.00
Shipping costs (to N.C.) 25.00
If you don't have the engine, it will cost you more. I'm in the process of doing my conversion, I'm going to start on my other Sami soon and will make the frame stronger. I don't think the stock axles will work that well, that's why I'm going with Dana 44's front and rear.
<font color=purple>Years back, I remember a few Sammi's running around with transplanted 3.8 Buick's. This is an even more compact engine than the 4.3 & you might look into the late-model 3800 engines from RWD Camaro's & Firebirds if you'd want to consider this instead. I think they're rated at 205HP & in a car, they provide fantastic performance & mileage. Just another thought on the subject of swaps.</font color=purple>