How the #$%! do you insert genetic code into a virus to produce a viral vector vaccine?

The AstraZeneca and Johnson&Johnson COVID 'vaccines' are supposed to be viral vector vaccines. The website of the Connecticut government explains quite well how they are supposed to work:

"In viral vector vaccines, spike protein DNA is placed inside a modified version of a different virus that doesn’t cause illness. This non-harmful virus delivers the DNA instructions to your cells – this virus is called the vector. Once your cells create the spike protein, your body breaks down the vector virus and removes it within a few days after vaccination."
https://portal.ct.gov/vaccine-portal/Vaccine-Knowledge-Base/Articles/mRNA-vs-Viral-Vector

Here is a question that almost nobody asks: How do you even make these types of vaccines?

A human hair has a diameter of about 100 micrometer (μm). Viruses supposedly have a size of about 80 nanometer (nm), so they are 1250x smaller than a human hair.

Virologists grudgingly admit that we don't have the technology to truly isolate viruses, i.e. truly separate them from their environment so that we only have virus particles and nothing else, because they're too small.

Can someone please explain to me how we don't have the technology to truly isolate viruses, but the geniuses at the pharmaceutical companies have somehow figured out technology to insert genetic material of our specifications into these nanoscopic particles?

Do they first isolate and then artificially inseminate these nanoscopic virus particles using injection needles with diameters in the picometer range?

If it's true that the required production technology does not currently exist, then viral vector vaccines cannot exist at this moment in time.

What CAN exist, however, is snake oil products, i.e. some other product that is marketed as being a viral vector vaccine. If this is true, these products are marketed by charlatans.

If the AstraZeneca and Johnson&Johnson COVID 'vaccines' are not viral vector vaccines, then what ARE they? Do they contain plasmids, i.e. genetic material in bacteria? Do the so-called genetic 'vaccines' even contain any genetic material or are they just toxins?

REFERENCES

https://en.wikipedia.org/wiki/Viral_vector_vaccine

https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/viralvector.html

SOURCE

https://rumble.com/v1gsxkr-dr.-lee-merritt-interviews-poornima-wagh-phd.html
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