CAD-COMPO

CAD-COMPO is a bundle made out of two very useful plug-ins for Adobe Illustrator. Basically, with the help of the BPT-Pro and the EXDXF-Pro plug-ins bundled within, you can transform the popular Adobe app from an app capable of handling mostly drawing-related tasks, into something that can also handle a fair degree of technical design.

Both included plug-ins can be installed with minimum fuss

To start taking advantage of what this bundle can offer, simply download the package, unzip the archive and install both plug-ins following typical wizard-based procedures.
As we've discovered during our tests, it's better to turn off Illustrator during this process.

The first plug-in makes Illustrator feel like a capable 2D-CAD utility

BPT-Pro brings to Illustrator a set of 19 neatly integrated and useful features in the Tools panel, organized in 8 sections with self-explanatory names. These categories include tools for precise angle, radius, diameters and other dimensions measuring, as well as a couple of editing and drawing tools for building arcs and fillets, for example.
There are two more interesting tools, one that allows you to quickly add the obligatory Title Block in your technical design projects, and one that allows you label any existing component.

The seconds plug-in is actually a very useful conversion DXF conversion tool

The second plug-in, EXDXF-Pro is slightly more unobtrusive, but you might argue, just as useful as the first. In plain words, this plug-in makes Illustrator a bit more "open" to working with AutoCAD projects as it offers better support for DXF files, all while fixing possible accuracy and compatibility issues.
If installed correctly, you should be able to notice it's presence each time you either import or export AutoCAD DXF projects.

Gives Adobe's Illustrator 2D-CAD superpowers

To conclude, if you're looking for a comprehensive solution towards making Adobe Illustrator more suitable for technical design and 2D-CAD-related work and not just leading drawing features, then CAD-COMPO might just fit the bill. Speaking of bills, as expected, it's more advantageous to buy the CAD-COMPO bundle than buying both packaged products separately, so that's something to keep in mind.